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Biomedical subjects

R F Clark

Publications and source records attributed to R F Clark.

At least 109 records · Page 6Linked to original sources
PubMed1975

Double-blind comparison of halcinonide and betamethasone valerate. Use with occlusive dressings in psoriasis treatment.

In a double-blind, paired-comparison study of the effectiveness of corticosteroid creams used under occlusion for the treatment of moderate to severe psoriasis, a new drug, halcinonide cream, was superior to betamethasone valerate cream, a steroid widely and effectively used for the treatment of psoriasis. This superiority was demonstrated in patients after both one and two weeks of treatment.

Administration, Topical↗
PubMedDate not supplied

The incidence of wound infection following crotalid envenomation.

Many sources advocate the empiric use of antibiotics to prevent wound infection (WI) following crotalid (rattlesnake) envenomations. We undertook a prospective observational study to examine the incidence of infections following crotalid envenomation. We studied crotalid envenomations presenting to our institution with follow-up by direct examination or telephone consultation. All patients presenting to our institution from June 1990 to October 1991 with history and clinical evidence of crotalid envenomation were included in the analysis. Routine management of crotalid envenomation was undertaken in each case, including the use of antivenin, surgical debridement, and antibiotics only when indicated by signs and symptoms of infection. A total of 54 patients were observed during the study period. Twelve patients received prophylactic antibiotics begun either prior to transfer to our institution or following a surgical procedure, and were evaluated separately. Follow-up was obtained on 32 patients 7 or more days following envenomation. Only 1 patient from the study group developed clinical evidence of WI during the study period. We conclude that because of a low incidence of WI in this series, the routine use of prophylactic antibiotics in such patients may not be warranted.

Adult↗
PubMedDate not supplied

The effect of cocaine and amphetamines on vital signs in trauma patients.

The object of this study was to determine if the presence of sympathomimetics (cocaine, benzoylecgonine, or amphetamine), detected by routine urine toxicology screen, affect the initial presenting pulse, blood pressure, respiratory rate, or level of consciousness in trauma patients. A retrospective chart review was performed on 1,679 patients enrolled in an urban level 1 trauma registry between October 1987, and July 1992, for whom complete toxicology data were available. There were no clinically significant differences in the vital signs of patients with positive toxicology screens and those with negative screens. There was a statistically significant increase in prehospital respiratory rate among patients with benzoylecgonine or amphetamines on admission toxicology screens when potential confounding factors were controlled. However, these effects disappeared upon arrival at the hospital. The detection of sympathomimetics by toxicology screening had no effect on pulse and systolic blood pressure when age, sex, mechanism, type, and severity of injury, prehospital IV fluid volume, and alcohol intoxication were controlled.

Amphetamines↗
PubMedDate not supplied

Neuroleptic malignant syndrome presenting without fever: case report and review of the literature.

The case of a patient with neuroleptic malignant syndrome (NMS) and delayed fever is presented. The patient was on lithium and trilafon before presentation to the emergency department with altered sensorium, rigidity, drooling, and tachycardia. The patient remained afebrile for 9 hours in the emergency department. He responded to treatment involving discontinuation of neuroleptics and bromocriptine. Typically NMS presents with a tetrad of fever, rigidity, altered sensorium, and autonomic dysfunction. This case is an example of NMS with delayed fever. A review of the literature on neuroleptic malignant syndrome is also presented.

Adult↗
PubMedDate not supplied

The management of sharps in the emergency department: is it safe?

In this study, we observed the management of sharps by health care workers including physicians, nurses, technicians, and students in the Emergency Department of the University of California-San Diego Medical Center. Twenty-eight percent of 418 observed sharp utilizations were managed in such a way that excess risk was conferred to the user, another person, or both. Twenty-seven percent conferred excess risk to the user and 12% to another person. Twenty percent of 322 recappable needles were recapped using a two-handed technique; 64% were disposed of uncapped. Four sharps (1%) were inadvertently thrown in the trash. Of the 418 observed sharp utilizations, none resulted in a puncture wound, although the four that were thrown in the trash represent a very high risk of injury to others. Physicians were observed handling the highest percentage of sharps in manners associated with excess risk while technicians and students managed sharps with the least risk. Among sharps used on patients who were IV drug abusers with unknown HIV status, 29% (n = 28) were handled with excess risk to the user, another person, or both. Of 24 sharps used on known HIV-infected patients, there were no practices observed that subjected either the user or another person to excess risk.

California↗
PubMedDate not supplied

Visine overdose: case report of an adult with hemodynamic compromise.

Imidazole decongestants are present in a variety of over-the-counter medications, including eye drops and nasal sprays. Their primary mechanism of action is vasoconstriction, accomplished by direct stimulation of alpha receptors on blood vessels. Accidental and intentional poisonings involving these substances are increasing, and can cause mental status and respiratory depression, as well as other effects related to alpha receptor stimulation. We present a case of tetrahydrozoline ingestion in an adult who presented with chest pain, bradycardia, mental status depression, miosis, and other signs and symptoms of imidazole compound poisoning. It is important for physicians to be familiar with the adverse effects of these ingestions and to be aware of the potential therapies for management.

Administration, Oral↗
PubMedDate not supplied

Meperidine: therapeutic use and toxicity.

Meperidine is a synthetic opioid analgesic frequently prescribed in the emergency department. Meperidine is most often administered intramuscularly or intravenously, due to its poor oral bioavailability, and is metabolized extensively by the liver. Analgesic effects usually last 3-4 hours with parenteral administration, and some adverse effects such as nausea may be reduced when meperidine is combined with antiemetic or antihistaminic medications. Although meperidine is often a preferred analgesic by both patients and physicians in the treatment of disorders such as migraine headaches, its analgesic efficacy has rarely proven superior to alternative parenteral pain medications in controlled trials. In addition, meperidine can precipitate monoamine oxidase inhibitor reactions, and during metabolism it is demethylated to normeperidine, a compound with significant central nervous system (CNS) toxicity. Meperidine should be considered a second line agent in the treatment of pain when opioid analgesics are required.

Analgesics, Opioid↗
PubMedDate not supplied

Prehospital use of activated charcoal: a pilot study.

Activated charcoal (AC) is most effective when administered soon after the ingestion of certain substances. Delays are recognized to occur at times in the administration of AC after arrival of poisoned patients in the emergency department (ED). In addition, it has been recognized that these delays may be avoided if AC administration is begun in selected patients by paramedics while en route to the ED. We present a pilot study evaluating the administration of AC to poisoned patients in the ambulance prior to arrival in the ED. We performed a retrospective review of Emergency Medical System (EMS) run sheets and ED records of poisoned patients during a 6-month period from two area hospitals. Cases were identified that met criteria for the prehospital administration of AC. Cases were divided into two groups: those who received prehospital AC, and those who did not. Groups were compared for ambulance transport time, time from first paramedic contact to AC administration, and whether AC was tolerated by the patient. A total of 14 patients received prehospital AC (group 1). This group was compared to 22 cases that would have qualified under County protocol to receive prehospital AC, but for whatever reason did not (group 2). Group 2 patients all received AC after arriving in the ED. Average ambulance transport times did not statistically differ among groups. The average time from first encounter with paramedics to administration of AC was 5.0 minutes when AC administration was given in the ambulance as compared to 51.4 minutes when delayed until arrival in the ED. Tolerance was similar among the groups. The time to initiate AC administration may be significantly shortened when begun by prehospital personnel. All EMS should consider including AC in protocols addressing the prehospital management of certain poisoned patients.

Ambulances↗
PubMedDate not supplied

Refining the level for anticipated hepatotoxicity in acetaminophen poisoning.

Treatment of an acetaminophen overdose with N-acetyl cysteine usually is based on the position of the 4-h acetaminophen (APAP) level on the Rumack-Matthew nomogram; however, there is disagreement on the level at which clinically relevant hepatotoxicity occurs. A retrospective review of all acute adult formulation APAP exposures reported to our poison center between 1986 and 1993 was performed and cases corresponding to the "possible risk or toxicity" range on the nomogram were identified. Our current poison center protocol for APAP poisoning does not recommend treatment with N-acetylcysteine (NAC) in low-risk patients if the 4-h serum APAP level or the extrapolated equivalent falls within the possible toxicity range on the nomogram. Seventeen cases met the inclusion criteria for the study and received no NAC; six additional patients met inclusion criteria but received one or two doses of NAC before therapy was discontinued. No patients in either group demonstrated clinical evidence of hepatotoxicity. This pilot study suggests that patients with no risk factors and APAP levels in the "possible risk" range may not require NAC therapy.

Acetaminophen↗
PubMedDate not supplied

Midazolam: a review of therapeutic uses and toxicity.

Midazolam is a familiar agent commonly used in the emergency department to provide sedation prior to procedures such as laceration repair and reduction of dislocations. Midazolam is also effective in the treatment of generalized seizures, status epilepticus, and behavioral emergencies, particularly when intravenous access is not available. Midazolam is often employed as an induction agent for rapid sequence endotracheal intubation. Midazolam has a rapid onset of action following intravenous, intramuscular, oral, nasal, and rectal administration. Only 50% of an orally administered dose reaches the systemic circulation due to extensive first-pass metabolism. Midazolam is metabolized by the cytochrome P450 enzyme system to several metabolites including an active metabolite, alpha-hydroxymidazolam. Cytochrome P450 inhibitors such as cimetidine can profoundly reduce the metabolism of midazolam. Midazolam has a half-life of approximately 1 h, but this half-life may be prolonged in patients with renal or hepatic dysfunction. Midazolam has been associated with respiratory depression and cardiac arrest when used in combination with an opioid, particularly in the elderly, although all ages are at risk for respiratory depression. Midazolam is relatively free of side effects when used alone and offers several advantages over traditional pharmacological agents such as chloral hydrate and the combination of meperidine, chlorpromazine, and promethazine. Hiccups, cough, nausea, and vomiting are the most commonly reported adverse effects. Many of the adverse effects associated with midazolam can be reversed rapidly by the administration of flumazenil, a competitive benzodiazepine receptor antagonist. Midazolam is a safe and effective agent for providing sedation in the emergency department.

Procedural Sedation↗
PubMedDate not supplied

Patients' satisfaction when denied authorization for emergency department care by their managed care plan.

We conducted a survey of managed care plan (MCP) patients who presented to the emergency department (ED) but were denied insurance authorization during a 3-month period. Patients were identified by triage or registration records, contacted by telephone after their visit, and surveyed regarding their satisfaction with the ED and MCP, follow-up care, and future behavior. We surveyed 72 (73.4%) of 98 subjects who were denied authorization. Forty-nine (68.1%) were redirected to a clinic or primary physician, 14 (19.4%) to an urgent care or other ED, and 9 (12.5%) were given no follow-up. Fifty-five respondents (76.4%) stated they had followed-up as directed, but 34 (47.2%) felt the delay had a negative impact. Thirty-nine (54.2%) were dissatisfied with their MCP. If their problems were to recur, 27 (37.5%) stated they would go to a clinic or call their MCP, but 34 (47.2%) would return to the ED. Many patients who are denied authorization are dissatisfied with their MCP and will return to the ED in the future, despite previous denials.

California↗
PubMedDate not supplied

A close look at fenfluramine and dexfenfluramine.

In an effort to combat obesity, several medications have been developed. The nonamphetamine anorectics, such as phentermine, fenfluramine, and dexfenfluramine, have been recommended as first-line drug therapy for the treatment of obesity once diet and exercise alone have failed. Numerous studies have shown that these agents can promote weight loss when combined with diet restriction and exercise. Although fenfluramine and dexfenfluramine lack the abuse potential of amphetamine and its congeners, these agents are associated with drug interactions and adverse effects. Concomitant administration of fenfluramine or dexfenfluramine with medications that enhance serotonin levels (e.g., antidepressants, monoamine oxidase inhibitors, and migraine medications) can precipitate serotonin syndrome. Sudden discontinuation of fenfluramine or dexfenfluramine after prolonged administration can precipitate withdrawal depressive symptoms. Primary pulmonary hypertension, a potentially fatal disorder, has been reported to occur approximately 30 times more frequently in patients receiving anorectic agents for more than 3 months compared to the general population. More recently, the association of these popular anorectics with valvular heart disease has caused increased concerns about their use. The risks of primary pulmonary hypertension, valvular heart disease, and the occurrence of convulsions, coma, and death in overdose appear to be equally likely with dexfenfluramine and fenfluramine. In addition, many patients who lose weight while taking these anorectics rapidly regain it after the medication has been discontinued.

Appetite Depressants↗